The present invention relates generally to a control system for an automotive vehicle. More specifically, the invention relates to a concentrated control system for an automotive vehicle suitable for a vehicle having a plurality of local control channels for an automatic power transmission, various engine control systems and so forth, which local control channels are designed to be controlled by electric control signals.
Objects to be controlled in the automotive vehicle are separated in a plurality of local control channels, such as for automatic power transmission control, engine control and so forth. In the conventional automatic transmission control system, for example, gear position is fixedly selected as a point on a two dimensional coordinate system which has one coordinate axis established in terms of a throttle valve open angle reflecting a torque demand and the other coordinate axis established in terms of a vehicle speed reflecting vehicle driving condition.
Among various automatic transmission control systems, there are some systems which have variable shifting point by selecting one of a plurality of shifting characteristics modes, such as power/economy and so for through manual operation of drivers through mode selector button and the like. Even in such type of the automatic transmission control system, selectable shifting criteria (shifting lines) are those sets for power mode and economy mode and cannot be varied sequentially between the shifting lines. Namely, in the above-mentioned type of the local control systems, fixed characteristics of controls are performed irrespective of the vehicular driving environmental condition.
Relevant arts associated with this technology can be seen in Japanese Unexamined Patent Publication (Kokai) No. 64-53047, Japanese Unexamined Patent Publication No. 1-113561 and Japanese Unexamined Patent Publication No. 2-37015, for example.
In the prior art, there is a problem in that, the local control channels are not established for sequentially variable control characteristics depending upon the vehicular driving environmental condition, and thus cannot precisely follow intended variation of the vehicular driving environmental condition as demanded by the driver and realize smooth variation of the control characteristics corresponding to the driver's demands or intent.